Acacia tortilis

Acacia tortilis (Forssk.) Hayne subsp. spirocarpa (Hochst. Ex A.Rich.) Brenan

Common names

Umbrella thorn (English); kafifi, fifi (Bemba); muzunga, mzunga, nsangu, nsangusangu, nyoswa, msasane, ngoka (Nyanja)

The specific and sub-specific Latin names refer to the twisted, spiral pods. The English name relates to the classic umbrella shape that this tree often takes.

General description and distinguishing characteristics

A tree up to 21 m in height which is often flat topped but may be rounded. Bark grey to black, fissured; young branchlets hairy becoming brown to purplish-black. Thorns hooked, up to 5 mm long, mixed with long, straight, whitish thorns (up to 8 cm long). Leaves compound, short, 2 cm long, with 2-10 pairs of pinnae, each bearing 6-19 pairs of leaflets. Leaflets very small, typically 0.5-2.5 mm long. Flowers cream or whitish in spherical heads, 5-10 mm in diameter (Dec-Feb). Fruit pods are contorted or spirally twisted, 6-9 mm wide, hairy with numerous dark red glands visible through a hand lens (May-Aug).

Range and habitat

Acacia tortilis subsp. spirocarpa occurs from Eritrea and Sudan southwards to southern Africa. In the Luangwa valley it is abundant in alluvial areas and on levees and sand deposits on the main rivers but elsewhere it is becoming less common because it is a heavily browsed species.